Skewer for cross wound bobbins with spring locking caps



June 27, 1933- 0. J. OBERMAIER SKEWER FOR CROSS WOUND BOBBINS WITH SPRING LOCKING CAPS Filed March 24, 1931 away/um s Owl 011mm Patented June 27, 193 3 UNITED STATES" PATENT OFFICE OTTO JULIUS OBERMAIER, OF NEUSTADT-ON-THE-HARDT, GERMANY SKEWER FOR CROSS WOUND BOBBINS WITH SPRING LQCKING CAPS Application filed March 24, 1931, Serial No. 525,012, and in Germany March 28, 1930.

On cross wound bobbin dyeing apparatus the cross wound bobbins are mostly placed on so called skewers and fixed by means of locking caps. The dye liquor is supplied into the spindles by pump pressure andso clamped that losses of pressure during the circulation of the dye are avoided.

Up to the present the locking caps have been so constructed that they are secured either by sliding springs or by screwthreads.

he sliding springs have not proved satisfactory, as they wear quicklypthe screw thread has however proved very satisfactory, but is inconvenient, as often many hundreds of bobbins are accommodated in a dyeing apparatus and the screwing on and off of the locking caps requires too much time. p

This invention provides a reliable locking cap, which holds securely and can be applied and removed quickly.

An embodiment of the invention is illustrated by way of example in the accompanying drawing in which:

Fig. 1 is a longitudinal section through a skewer, carrying a bobbin and fitted with a locking cap according to the invention.

Fig. 2 is a top plan view of the locking cap.

Fig. 3 shows the locking cap in elevation seen from the left of Fig. 1.

After the cross wound bobbin 7) has been placed with its sleeve it on the skewer s, the locking cap is is pressed thereon. For this purpose the skewer s has at its upper end 8 tooth-shaped annulargrooves z interrupted at one point by a vertical groove n as shown in Figs. 1 and 2. The locking cap is has a plurality of spring hooks f f 7%, designed to engage in the tooth shaped grooves z and arranged so that they spring back on the cap being pressed downwards, but immediately thereafter catch and hold the cap is tightly, when pressure is exerted in the direction for removing the cap. Consequently the cap can only be removed, if it is turned until the spring hooks engage with the vertical groove a. At this point the spring books do not encounter any resistance, and the cap can be pulled off. i p I In order to ensure that the sleeve h is always tightly clamped'between the cone 0 on the spindle and the cone 0 at the lower end of the capone spring hook is not sufficient for the following reason. As the distance between the tooth shaped grooves .2 and the. bottom of the sleeve it can never be absolutely uniform, it might happen, for example,

- that the cone 0 already bears tightly at the pointa (Fig. 1), whereas, if only one spring hook is employed, this comes into the position of the spring hook f (Fig. 1), that is, does not engage. In the event of pressure being exerted by the skewer 8, this pressure be pushed in the direction of the arrow until the spring hook engages in the next annular groove. a between the sleeve 1. and the cone 0 so that the pressure becomes lost.

By the employment of a plurality of springs of different length, this objection can be overcome. If for example the distance between the teeth formed by the annular grooves 2 is three mms, three springs differing one mm. in length might be employed, so that only an error of one mm. can occur. This one mm. is however of no importance in practice and can be reduced to a minimum by providing more springs.

The employment of a plurality of springs presents the further advantage, that they wear less quickly and, if a tooth should break 05, the other teeth can still serve as holding means.

When the cap is being put on the springs are allowed to slide over the teeth, formed by the annular grooves 2 until the cap sits securely. suflioient to turn same through a partial rotation until the spring hooks f f f engage in the longitudinal grooves n. Both operations, that is the putting on and removing of the cap, can be effected in the shortest space of time.

I claim Consequently a gap might occur at k 'is communicated to the cap is, which would I In order to remove thecap, it is I 1. A device for fitting and securely holding cross wound bobbins on dyeing skewers an annular recess therein; a locking cap on the skewer; and a plurality of longitudinally disposed yieldable members of different lengths on the cap whereby at least one member will engage the recess. I

3. In a combination as set forth in claim 2, a longitudinal groove intersecting the recess and extending to the end of the skewer, whereby when the cap is rotated themembers will enter the longitudinal groove and permit removal of the cap.

4. In combination with a bobbin; a skewer rotatably supporting the bobbin and having a longitudinal series of spaced annular recesses therein; a locking cap on the skewer; and a plurality of longitudinally disposed yieldable members on the cap spaced longitudinally apart a distance different from the spacing of the recesses whereby at least one member will engage a recess.

5. In a combination as set forth in claim 4, a longitudinal groove intersecting all the annular recesses and extending to the end of the skewer, whereby when the cap is rotated the members will enter the longitudinal groove and permit removal of the cap.

6. In combination with a bobbin; a skewer rotatably supporting the bobbin and having a longitudinal series'of evenly spaced annular grooves therein; a locking cap on the skewer; and a series of evenly spaced 1ongitudinally disposed yieldable members on the cap, the spacing of the members being less than the spacing of the grooves, whereby at least one member will engage a groove.

7. In a combination as set forth in claim 6, a longitudinal groove intersecting all the annular grooves and extending to the end of the skewer, whereby when the cap is rotated the members will enter the longitudinal groove and permit removal of the cap.

8. In a combination as set forth in claim 6, said yieldable members comprising paral lel spring hooks extending through an opening in the side of the cap.

In testimony whereof I affix my signature.

OTTO JULIUS OBERMAIER. 

